The employment of air purification plants is of great importance particularly in the textile industry, since large amounts of dust and fluff are released into the air in the course of manufacturing textile products. This has a significant negative influence on the quality of the manufactured textile product when such contaminants are deposited on the textile yarn. For this reason, filtration plants are usually employed in textile manufacturing facilities, in order to free the air from dust and material particles carried therein. Such filtration installations usually fill rooms and have filter walls which are meters high, having filter mats which are passed though by the air to be purified. In this manner, the dust and fiber particles carried in the dirty air are separated at the filter mats. However, the amount of deposits of separated particles, which increases in the course of the service life of the air purification device, goes hand-in-hand with a decrease in the permeability of the filters. In order for a constant filtration performance to be able to be ensured, the filter faces must therefore be cleaned at regular intervals or freed from deposited dust and fiber materials. Known cleaning possibilities include, for instance, back-washing or reverse-flow blowing, scraping, beating or suctioning the filter faces.
For example, DE 3 527 656 A1 discloses a scraper which for cleaning the filter face is moved up and down along the surface of the latter, so as to scrape off the particles which are deposited on the filter face and to convey said particles into a receiving space which lies therebelow.
However, such scrapers haven proven to be disadvantageous for air purification plants in the textile industry, as on account of electrostatic charging the fibers carried in the air stream increasingly build up to form comparatively large accumulations—so-called fiber plaits. These fiber plaits often cling to the scraper, severely hindering the ability of the latter to function.
For this reason, suction devices which are moved along the filter faces are increasingly employed in the textile industry for suctioning off the deposited contaminants from the filter faces.
For instance, DE 3830991 discloses a filtration device which has a trap device having a plurality of V-shaped niches which are effective in filtration. In order to clean the niches, the suction nose of a suction element which is fastened on a support is introduced into a niche on the front side and moved up and down in said niche. Each niche is either assigned one dedicated suction element, or one suction element handles cleaning of a plurality of niches and upon cleaning-down of a niche is reversed therefrom, moved laterally in a horizontal manner outside the trap device to a next niche and inserted into the next niche with the suction nose leading. For cleaning the niches and for switching from one niche to another, the suction elements or their supports, respectively, are thus moved in three spatial directions—namely up and down in the vertical direction within the niches; back and forth in the horizontal direction, and laterally to and fro. Not only constructively complex designs but also complicated drive and control systems are required in order to be able to implement such multidimensional movement profiles. Moreover, a lot of space is required outside the filter niches of the trap device for maneuvering the suction element from one niche to the next.
A further problem in the context of suction installations in air purification plants lies in that excessive fiber and dust accumulation arises over time in particular at points which are not or only poorly accessible to the suction nozzles, which may lead to congestion and thus to blockage of the suction nozzle.